Senator Kay Hagan (D-NC) has a bit of an unhealthy obsession. By the looks of her supporter emails, it seems she can’t get two people out of her head: the Koch brothers. In fact, 19 of her campaign’s last 21 emails have mentioned those mean old, rich Kochs.

It started with this alarming message in July:

Dear Friend,

Most people pay attention to politics in a Presidential election year. But let me tell you, folks: This year’s midterm elections are just as important as any Presidential year. And I’m not just saying that because I’m one of the Senators up for re-election.

It's clear that the Koch brothers, Karl Rove, and the special interests want to get more of their allies elected to Congress. Special interest groups have already spent more than $17 million to defeat me. And to Karl Rove and the Kochs, I’m their top target.

The urgent email came a few months after Americans for Prosperity, a group co-founded by the Kochs, spent $8.2 million on TV, radio and digital ads against Hagan, slamming the senator for her cozy camaraderie with the president.

These ads are not without due cause. As the videos mention, Hagan votes with the president 96 percent of the time and has been a vocal supporter of his disastrous health care law, even as recent as this past May.

It’s not just in the cyber world Hagan has barked at the Koch ads. In an interview with Chris Hayes on MSNBC, she insisted North Carolinians aren’t buying the Kochs' claims:

“The people of North Carolina are not going to let the Koch brothers buy this seat. My state is being flooded with millions of dollars from this outside interest group.”

In more recent emails, Hagan lambasted the Kochs for giving her Republican opponent Thom Tillis the maximum amount allowed under federal law.

"The Kochs are trying hard to make this election about who they want to be our next Senator. But North Carolinians get to decide this race -- not the Kochs."

Hagan should be careful what she wishes for. The poll tracker on the Huffington Post shows an increasingly close contest, with Tillis gaining steadily on Hagan.

The Kochs know a thing or two about being targeted. Critics routinely lambast them for their wealth and power. The studio Brave New Films even made a movie about them, "Koch Brothers Exposed," to paint them as the “poster boys for the 1 percent” and accusing them of “fueling inequality in America.”

Should the Kochs be ashamed of their wealth? Of course not. Contrary to liberal beliefs, the Kochs did not get rich on the backs of the poor. The American Conservative offers a comprehensive history of how the brothers went from mending fences and being treated like “lowly cowhands” on their father’s ranches to eventually become the successful businessmen they are today.

You won’t get those details in a Kay Hagan email.

Instead of talking incessantly about the Koch brothers, why doesn’t Hagan focus on her policy achievements or plans for the future?

On second thought, maybe her initial tactic isn't such a bad idea after all.